Coal drill



Sept. 13, 1927.'

COAL DRILL Filed May 2, 1925 2 Sheets-Sheet l Sept. 13,1927- AVBELJ COAL DRILL Filed May 2. 1925 2 Sheets-Sheet 2 Patented Sept. 13, 19.27.

'JOSEPH AY'BELJ, 0F BRIDGEPORT, OHIO.

COAL DRILL.

Application led May 2,

This invention relates to an improved coal drill for use in coal mines,`it having reference to the type of drill employed for drilling a hole in the wall of the coal for 'preception of an explosive for blasting purposes.

Thev inventionl is characterized by a supporting vframe upon which a carriage is mountedfor reciprocation, there being intermeshinggearing between the carriage and frame for moving the carri'ageleither toward or from the wall, and for simultaneously rotating a drill holder.

The specific structural details for carrying this into effect will become apparent from the following. description and drawings.

nthe Aaccompanying drawings forming a part of this application, and in which like numerals are employed to designate like parts throughout the same:

n Figure 1 is a side View in section and elevation of a coal drilling machine constructed in accordance with the present invention.

Figure 2 is atop plan view of the same.

Figure 3 is a central longitudinal section with portions in elevation.

Figure 4'is a detail View of a key and retainer therefor.

Figure 5 is a section taken approximately upon the plane of the line 5-5 of Figure 4.

Referring to the drawings in detail, the reference character 1 designates an elongated supporting frame, the opposed side bars of which are provided on their undersides with rack teeth 3. Detachably fastened to the front cross bar of the frame is an anchoring spur 4 adapted to be embedded in the wall 5 in which the hole is to be drilled.` Hingedly connected at 6 to the opposite end bar of the frame are jacks 7 each of which embodies an internally screw threaded socket 8 having a pointed and screw threaded stem 9 operating therein. It should be noted that the arrangement of the hinges is such as to permit the angularity of the two acks to be varied considerably with respect to the frame to permit them to be effectively engaged with the top and bottom walls 10 and 11 respectively of the mine.

lso supported by the front bar of the frame is an appropriate upstanding guide 12, for the drill bit 13.

Mounted for reciprocation upon the suporting frame is a carriage designated as a whole by the reference character 14. This 1925.l Serin No. 21490.

carriage in' itself is in the form of a frame, and is of peculiar configuration in order to provide clearance, and yet provide anl appropriate mounting for the various details which it carries. The `front wall for instance is shaped to straddle the side bars of t-he frame, and the front wall carries a rotary drill holder 15 which is journaled in the bearing opening therein and provided on its inner end with a beveled pinion 16. This pinion meshes with 'the beveled teeth of a beveled gear 17 carried by a shaft 18`journaled upon the carriage. Fixedly mounted on this same shaft 18 is a small spur gear 19 which is in mesh with a chain of gearing including the relatively large gear 21 and slightly smaller gear 21a. VThe gear 21a is mounted on a shaft 22, carrying a pinion 23 at each end. The pinions 23 are in mesh with medium sized gears 24 j ournaled upon the side walls of the carriage vand in mesh with the teeth of the side bars of the frame 1. Obviously, this train of gearing which also includes a toothed gear wheel 25 is employed for reciprocating the carriage. In this connection it will be noted that the gear wheel 25 is mounted on the main operating shaft 26, the larger gear 21 being keyed upon this shaft. By referring to Figure 5, it will be noted that a sliding pin 27 forms a key, this being carried by the gear 21 and adapted for a reception in a hole 28 formedin the gear wheel 25. The pin is headed as indicated at 28 and a key-engaging member 30 is formed on the shaft for the reception of the headv to hold the pin in a retracted or ineffective condition; it being understood in this connection that the shaft 26 and the gear 21 rotate as one piece.

In practice, theframe 1 is disposed in a horizontal position above the floor of the mine, and the spur 4 is driven slightly into the wall 5 to anchor and support the forward end of the frame. Now the jacks 7 are adjusted and engaged with the top and bottom walls in a customary way, and the frame is properly supported in operating position. If the device is to be operated by hand as Wil-l frequently be. the case, a hand crank 31 will be att-ached to the extended end of the shaft 26. Now the shaft will be rotated and it is obvious that through the main gear 21 and spur gear and beveled gearing, the drill holder 15 will be rotated to rotate the drill 13 for boring a hole in the wall. If the key 27 has been projected into the opening 28 in the gear wheel 25 it will be seen that the rotation ofthe shaft 26 will simultaneously operate upon the train of gearing to bodily move the` carriage upon the side rails of the` frame, so that while the drill is rot-ating the carriage will be fed toward the wall to follow up the drilling operation. It is obvious that the direction of movement of the shaft 26 controls the direction of movement of the carriage. By withdrawing the key 27 however the gearing train will not come into play and the carriage will remain substantially sta-- tionary.

Y The provision ofthe clutch member 27 also permits withdrawal of the bit 13 from a drill hole without rotating the bit, since on completion of a hole, the clutch can be disengaged and the carriage 14 slid back, the gears 2la and 24 idling during such withdrawing movement. if the clutch were in operative position during this rearward movement of the carriage, the drill bit would be rotated with an unscrewing action, leaving chipsl or powdered coal within the hole, thus interfering with the introduction of an explosive charge. By drawing the drill back without simultaneously rotating the same, the cuttings arey all drawn from the drill hole.

It is thought that the description considered in connection with the drawings will enable persons vskilled in the art to which the invention relates to obtain a clear understanding of the same. Therefore, a

more lengthy description is thought unnecessary.

While the preferred embodiment of the invention has been shown and described, it is to be understood that minor changes coming within the field of invention claimed may be resorted to if desired.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is A coal drilling machine comprising in combination a hollow substantially rectangular shaped supporting frame having gear teeth formed thereon to constitute a rack, a drill carriage supported by and adapted for movement on said fra-me and having a gear wheel journalled therein which interacts with t-he teeth of the supporting frame to constitute a lower bearing support, a drill kholder journalled in said carriage, a drive shaft rotatably jounalled therein, a train of gear wheels operatively connecting said drill holder and drive shaft, a train of gear wheels connecting said rack engaging gear wheel and the said drive shaft, means for interconnecting said gear trains to simultaneously rotate said drill holder and feed the carriage at a speed proportionate to the cutting speed of the drill and for disconnecting the same to render said drill holder operative independently of said feed mechanism, all of the gear wheels of said trains being in constant mesh whether they .are jointly or severally operated.

in testimony whereof I alixv my signature.

JOSEPH AVBELJ. 

